Chester Floyd Carlson (February 8, 1906 – September 19, 1968) was an American physicist, inventor, and patent attorney born in Seattle, Washington.
Carlson invented electrophotography (now xerography, meaning "dry writing"), producing a dry copy in contrast to the wet copies then produced by the Photostat process; it is now used by millions of photocopiers worldwide.
Early life
Carlson's father, Olaf Adolph Carlson, had little formal education, but was described as "brilliant" by a relative. Carlson wrote of his mother, Ellen, that she "was looked up to by her sisters as one of the wisest."
When Carlson was an infant, his father contracted tuberculosis, and also later suffered from arthritis of the spine (a common, age-related disease). When Olaf moved the family to Mexico for a seven-month period in 1910, in hopes of gaining riches through what Carlson described as "a crazy American land colonization scheme," Ellen contracted malaria. Because of his parents' illnesses, and the resulting poverty, Carlson worked to support his family from an early age; he began working odd jobs for money when he was eight. By the time he was thirteen, he would work for two or three hours before going to school, then go back to work after classes. By the time Carlson was in high school, he was his family's principal provider. His mother died of tuberculosis when he was 17, and his father died when Carlson was 27.
Carlson began thinking about reproducing print early in his life. At age ten, he created a newspaper called "This and That", created by hand and circulated among his friends with a routing list. His favorite plaything was a rubber stamp printing set, and his most coveted possession was a toy typewriter an aunt gave him for Christmas in 1916—although he was disappointed that it was not an office typewriter.
While working for a local printer while in high school, Carlson attempted to typeset and publish a magazine for science-minded students like himself. He quickly became frustrated with traditional duplicating techniques. As he said in a 1965 interview, "That set me to thinking about easier ways to do that, and I got to thinking about duplicating methods."
Education
Because of the work he put into supporting his family, Carlson had to take a postgraduate year at his alma mater San Bernardino High School to fill in missed courses. He then entered a cooperative work/study program at Riverside Junior College, working and going to classes in alternating six-week periods. Carlson held three jobs while at Riverside, paying for a cheap one-bedroom apartment for himself and his father. At Riverside, Chester began as a chemistry major, but switched to physics, largely due to a favorite professor.
After three years at Riverside, Chester transferred to the California Institute of Technology, or Caltech—his ambition since high school. His tuition, $260 a year, exceeded his total earnings, and the workload prevented him from earning much money—though he did mow lawns and do odd jobs on weekends, and work at a cement factory in the summer. By the time he graduated, he was $1,500 in debt. He graduated with good—but not exceptional—grades, earning a B.S. degree in physics in 1930, at the beginning of the Great Depression. He wrote letters seeking employment to 82 companies; none offered him a job.
Early career
As a last resort, he began working for Bell Telephone Laboratories in New York City as a research engineer. Finding the work dull and routine, after a year Carlson transferred to the patent department as an assistant to one of the company's patent attorneys.
Carlson wrote over 400 ideas for new inventions in his personal notebooks while working at Bell Labs. He kept coming back to his love of printing, especially since his job in the patent department gave him new determination to find a better way to copy documents. "In the course of my patent work," wrote Carlson, "I frequently had need for copies of patent specifications and drawings, and there was no really convenient way of getting them at that time." At the time, the department primarily made copies by having typists retype the patent application in its entirety, using carbon paper to make multiple copies at once. There were other methods available, such as mimeographs and Photostats, but they were more expensive than carbon paper, and they had other limitations that made them impractical. The existing solutions were 'duplicating' machines—they could make many duplicates, but one had to create a special master copy first, usually at great expense of time or money. Carlson wanted to invent a 'copying' machine, that could take an existing document and copy it onto a new piece of paper without any intermediate steps.
In 1933, during the Great Depression, Carlson was fired from Bell Labs for participating in a failed "business scheme" outside of the Labs with several other employees. After six weeks of job-hunting, he got a job at the firm Austin & Dix, near Wall Street, but he left the job about a year later as the firm's business was declining. He got a better job at the electronics firm P. R. Mallory Company, founded by Philip Mallory (which became the Duracell division of Procter & Gamble), where Carlson was promoted to head of the patent department.
The invention of electrophotography
In 1936, Carlson began to study law at night at New York Law School, receiving his LL.B. degree in 1939. He studied at the New York Public Library, copying longhand from law books there because he could not afford to buy them. The pains induced by this laborious copying hardened his resolve to find a way to build a true copying machine. He began supplementing his law studies with trips to the Public Library's science and technology department. It was there that he was inspired by a brief article, written by Hungarian physicist Pál Selényi in an obscure German scientific journal, that showed him a way to obtain his dream machine.
Carlson's early experiments, conducted in his apartment kitchen, were smoky, smelly, and occasionally explosive. In one set of experiments, he was melting pure crystalline sulfur (a photoconductor) onto a plate of zinc by moving it just so over the flame of his kitchen stove. This often resulted in a sulfur fire, filling the building with the smell of rotten eggs. In another experiment, the chemicals he was working with caught fire, and he and his wife were hard-pressed to extinguish the flames.
During this period, he developed arthritis of the spine, like his father. He pressed on with his experiments, however, in addition to his law school studies and his regular job.
Having learned about the value of patents in his early career as a patent clerk and attorney, Carlson patented his developments every step along the way. He filed his first preliminary patent application on October 18, 1937.
By the fall of 1938, Carlson's wife had convinced him that his experiments needed to be conducted elsewhere. He rented a room on the second floor of a house owned by his mother-in-law at 32-05 37th Street in Astoria, Queens. He hired an assistant, Otto Kornei, an out-of-work Austrian physicist.
Carlson knew that several major corporations were researching ways of copying paper. The Haloid Company had the Photostat, which it licensed to Eastman Kodak, the photography giant. However, these companies were researching along photographic lines, and their solutions required special chemicals and papers. The Photostat, for instance, was essentially a photograph of the document being copied.
Electrophotography
Selényi's article described a way of transmitting and printing facsimiles of printed images using a beam of ions directed onto a rotating drum of insulating material. The ions would create an electrostatic charge on the drum. A fine powder could then be dusted upon the drum; the powder would stick to the parts of the drum that had been charged, much as a balloon will stick to a static-charged stocking.
To this point, Carlson's apartment-kitchen experiments in constructing a copying machine had involved trying to generate an electric current in the original piece of paper using light. Selényi's article convinced Carlson to instead use light to 'remove' the static charge from a uniformly-ionized photoconductor. As no light would reflect from the black marks on the paper, those areas would remain charged on the photoconductor, and would therefore retain the fine powder. He could then transfer the powder to a fresh sheet of paper, resulting in a duplicate of the original. This approach would give his invention an advantage over the Photostat, which could create only a photographic negative of the original.
On October 22, 1938, they had their historic breakthrough. Kornei wrote the words "10.-22.-38 ASTORIA." in India ink on a glass microscope slide. He prepared a zinc plate with a sulfur coating, darkened the room, rubbed the sulfur surface with a cotton handkerchief to apply an electrostatic charge, then laid the slide on the plate, exposing it to a bright, incandescent light. They removed the slide, sprinkled lycopodium powder to the sulfur surface, softly blew the excess away, and transferred the image to a sheet of wax paper. They heated the paper, softening the wax so the lycopodium would adhere to it, and had the world's first xerographic copy. After repeating the experiment to be sure it worked, Carlson celebrated by taking Kornei out for a modest lunch.
Kornei was not as excited about the results of the experiment as Carlson. Within a year, he left Carlson on cordial terms. His pessimism about electrophotography was so strong that he decided to dissolve his agreement with Carlson that would have given Kornei ten percent of Carlson's future proceeds from the invention and partial rights to the inventions they had worked on together. Years later, when Xerox stock was soaring, Carlson sent Kornei a gift of one hundred shares in the company. Had Kornei held onto that gift, it would have been worth more than $1 million by 1972.
The road to Carlson's success—or that for xerography's success—had been long and filled with failure. He was turned down for funding by more than twenty companies between 1939 and 1944. He tried for some time to sell the invention to International Business Machines (IBM), the great vendor of office equipment, but no one at the company saw merit in the concept—it is not clear that anyone at IBM even 'understood' the concept. His next-to-last attempt to garner the interest—and funds—he needed to commercialize the physics was a meeting with the Department of the Navy. The Navy had a specific interest in the production of dry copies, but they did not "see" what Carlson saw.
On October 6, 1942, the Patent Office issued Carlson's patent on electrophotography.
Battelle Memorial Institute When Carlson was close to giving up on getting his invention from a proof-of-concept to a usable product, happenstance provided a solution. In 1944, Russell W. Dayton, a young engineer from the Battelle Memorial Institute in Columbus, Ohio, visited the patent department at Mallory where Carlson worked. Dayton, brought in as an expert witness in a patent appeal case by Mallory, seemed to Carlson to be "the kind of fellow who looked like he was interested in new ideas." Although Battelle had not previously developed ideas generated by others, Dayton was fascinated by Carlson's invention. When Carlson was invited to Columbus to demonstrate his invention, Dayton's statement to the Battelle scientists and engineers present showed that he understood the importance of Carlson's invention: "However crude this may seem, this is the first time any of you have seen a reproduction made without any chemical reaction and a dry process."
Battelle took a risk on Carlson's invention, which seemed to come out of nowhere: